Measuring crime prevention outcomes

What people want to know about a crime prevention initiative is 'did it work?' That is, did it achieve its intended outcome by preventing or reducing the targeted crime and if so, by how much?

CRM 38 introduced the four main elements necessary for building a performance measurement system: inputs, processes, outputs and outcomes. Crime prevention performance measurement has tended to focus on what made an initiative happen (inputs) or the activity it produced (outputs). As a result, program managers are often better at accounting for the amount of money spent and the amount and type of activity undertaken than they are at reporting on results (outcomes). As the figure below shows, inputs and outputs are easier to measure because they are easier to count and this is generally within the direct control of program managers. However, while inputs, processes and outputs matter, measuring outcomes (or the crime prevention impact) is what really matters.

Measuring program outcomes is not always straightforward. For one thing, the important outcome measures may not be readily quantifiable. For example, a local shopping centre may introduce security guards in order to reduce shop-theft, prevent antisocial behaviour and improve the community's overall perception of the centre as safe. It is relatively easy to measure the impact of the extra security on shop-theft and antisocial behaviour by counting the number of attempted and actual incidents in the shopping centre before and after the security guards arrived. However, it may be more difficult (and costly) to assess the local community's overall perception of crime in and around the shopping centre. It is important to know if they feel safe because they decide whether to shop there and so generate income for the centre's businesses.

One way to assess the community's confidence in the shopping centre as a safe place could be by measuring changes in turnover and customers. But seasonal issues or other commercial and external factors such as neighbouring shopping centres activities may affect this and therefore need to be taken into account. Alternatively (or additionally), a more direct outcome measure could be a survey of customer confidence before and after the extra security is introduced. However, this can be expensive and may also be influenced by external factors.

A balanced performance measurement framework built on a range of measures focused on outcomes will help program managers to better understand the factors that are influencing their program's performance and its effectiveness.

The relative importance of and control over performance measures

Further reading

  • Fiscal Policy Studies Institute 2004. Results and performance accountability, decision-making and budgeting: RBA 101 PowerPoint presentation. http://www.resultsaccountability.com/powerpoint_-_rba_101.htm (viewed 3 January 2006)
  • Tilley N 1995. Thinking about crime prevention performance indicators. Crime prevention and detection series paper no. 57. London: Home Office